Papers by Keyword: Notch Wear

Abstract: Inconel 718 is a material exhibiting characteristic that are able to maintain strength and integrity at elevated temperatures, but it is well known as a material with poor machinability. This paper presents a study of the performance in high speed machining of TiAlN/AlCrN nanomultilayer PVD coated Inconel 718 with minimum lubrication. Investigations have been made into the effects of cutting speed, feed rate and depth of cut (DOC) on the tool life. A toolmakers microscope and a scanning electron microscope (SEM) were used to examine the tool wear and chemical attrition, respectively, on the cutting tool during machining. In the machining of aged Inconel 718, the cutting tool experienced attrition, abrasion and notch wear throughout the experiment. Notch wear was found to be the dominant failure mode during milling; this wear appeared severe when localized flank wear reached the critical zone. The influence of radial depth despite the cutting speed, well known as having the most significant effect on tool life, is also discussed.

Abstract: The present paper is an attempt of an experimental investigation on the machinability of superalloy, K424 during high speed turning using different ceramic inserts under different cutting speed and cooling/lubricating condition. The effect of machining parameters on the tool wear was examined through SEM micrographs.The experimental results show that, round Al2O3＋SiCW KY4300R ceramic insert shows the best cutting performance in cutting the superalloy K424 , and it should be used in rather higher speed. Cold nitrogen gas is not recommended when machining nickel-based alloy with ceramic tools. SEM and EDS analysis shows that the ceramic tool was severely controlled by tool nose and depth-of-cut notch wear, followed by flaking and chipping.